Yan'an Shi1972BooksJi suan ji fan zui yi nan wen ti si fa dui ceDa an zheng houXing shi guan xia zhi du shi yongDa an xing shiZhongguo 2010 nian zui shou guan zhu xing shi an jian ping dianJian si jiZhongguo xing shi zheng ce zhuan ti zheng liAuthor data: Open Library